The HTML button elements we use are all regular buttons that don't
submit form data to a server. According to
https://developer.mozilla.org/en-US/docs/Web/HTML/Element/button#notes
those buttons should all have their type set to `button` explicitly, but
we only do that a handful of them. This commit fixes the issue by
consistently giving all our buttons the `button` type.
Co-authored-by: Calixte Denizet <calixte.denizet@gmail.com>
f1f58bbe67
